By Jan H. Schut
ANTEC, the world’s premier plastics technology conference, turns 70 this year. Co-located with the National Plastics Exposition April 2-4 at the Orange County Convention Center in Orlando, Fla. (www.antec.ws), it will present 600 technical papers, three plenary sessions, three New Technology Forums, and the Fundamentals Fellows Forum (www.4spe.org/sites/default/files/antec12-finalprogram.pdf). Here’s a look at some of the new technology highlights.
Some of the biggest news is nano-sized, including unusual nano-layer films, foamed and nanoporous fibers, nano mold tooling features, and some unusual new nanomaterials. A whole new type of extruder, which uses a rotor and vanes, is described, which will also be displayed for the first time at NPE. Several papers describe novel extruded and injection molded foaming technologies, including use of water as a physical blowing agent. Materials news includes a new lignin thermoplastic and a less expensive way to make PEK.
The letter and number in brackets after the title of a paper indicate the day of the week and session when that paper will be given, i.e., [T23] will be session 23 on Tuesday, April 3. For those who don’t attend, copies of all ANTEC papers are also available at or after the show on a CD from the SPE (www.4spe.org. Member price is $50, non-member price is $100. But then you don’t get to meet the inventors.
EXTRUSION AND FILM
Gas Permeability of Poly (4-Methylpentene-1) in a Confined Nanolayered Film System [T16] by Guojun Zhang, Case Western Reserve University, Cleveland, Ohio (www.case.edu). Layer multiplying coextrusion of nanolayer P4MP1 and syndiotactic PS crystallizes the P4MP1 layers into bundles of lamellae perpendicular to the film surface. Instead of a barrier, this novel structure creates open cross channels, which increase oxygen permeability.
Layer Multiplying Coextrusion of Polylactic Acid and Polyvinyl Alcohol Cast Films [M19] by Jo Ann Ratto, U.S. Army Natick RD & E Center, Natick, Mass. (nsrdec.natick.army.mil). Food packaging films cast with up to 145 alternating layers of PLA and PVA combine high oxygen barrier and mechanical properties with biodegradability. No American trash left behind!
Experimental Investigations on Vane Extruder for Polymer Short Thermo-Mechanical History Processing [T23] by Qu Jin-ping, South China University of Technology, Guangzhou, China (en.scut.edu.cn). First presented at ANTEC 2009, this novel extruder (Pat. WO 2009/094815) has vanes on a rotor instead of channels on a screw, which “totally alters the shear conveying mechanism” vs. conventional extrusion. Instead of solids compacting, conveying, and melting sequentially like a conventional extruder, the vane extruder compacts, conveys, and melts simultaneously. Heat history is shorter and mixing reportedly better. A vane extruder will be displayed for the first time in the U.S. at NPE Booth 47013 on a line to make corrugated plastic sheet. The vane is apparently also being applied to injection molding (Patent # WO 2012/003670).
The Effect of Polyhydroxybutyrate-co-valerate (PHBV) Content on Thermal, Rheological, Mechanical Properties and Foaming Behavior of Polylactic Acid (PLA) [T35] by Qi Guan, University of Toronto in Canada (www.utoronto.ca). Foaming an immiscible combination of PLA and up to 30 wt % PHBV leads to finer, more homogeneous foam morphology than PLA alone.
Experimental Study on Rubber-Assisted Embossing of Micro Fluidic Chips [T31] by Danyang Zhao of Dalian University of Technology in China (www.dlut.edu.cn/en). A thin polymer film is micro-thermoformed with a rubber plug assist to form micro channels, then sealed with transparent adhesive film to make a flexible micro fluidic chip.
‘Pull and Foam’ Injection Molding Method: Foamed Ribs for Stiffening Plane Components [M35] by Mike Tromm, University of Kassel in Germany (www.uni-kassel.de). Uni-Kassel and 3 Pi Consulting & Management (www.3-pi.de) in Paderborn developed a process to mold stiffer parts by combining solid surfaces and sections of a part with foamed ribs, molded in a single step. Solid areas cool first; then core pulls in the mold retract; and the foam expands.
Improving Surface Quality of Foamed Polycarbonate (PC) Parts Using Water as the Physical Blowing Agent [W9] by Jun Peng, University of Wisconsin-Madison (www.wisc.edu). Salt dissolved in water is fed into the hopper with PC pellets to make micro-cellular foam injection molded parts. The water acts as a physical foaming agent, the salt as a nucleating agent.
Dynamic Behavior and Experimental Validation of Cell Nucleation and Growing Mechanism in Microcellular Injection Molding Process [M35] by Chao-Tsai Huang, CoreTech System (Moldex3D) in Hsinchu, Taiwan (www.moldex3d.com). CoreTech and Trexel Inc. (www.trexel.com) have jointly developed new mold simulation for Trexel’s Mucell microcellular foam injection molding process.
Ultraprecision Mold Manufacture for Micro Injection Molded Micro Optics [T31] by Lars Schoenemann of Bremen University in Germany (www.uni-bremen.de). Recently developed diamond micro chiseled molds can form micro optic parts with prismatic microstructures between 50 and 500 nm.
NEW MATERIALS AND COMPOUNDS
Comparative Studies on the Crystallization Behavior of Poly Ether Ketone (PEK) [M17] by Mathew Abraham, Gharda Chemicals Ltd., Mumbai, India (www.gharda.com). PEK synthesized by Gharda “using cheap chlorine-based monomers” (Pat. Applic. # EP20070253498 in 2010), is compared to PEK introduced by Victrex PLC in the U.K. (www.victrex.com) in 1999 “using expensive fluorine-based monomers” and reportedly is comparable. Actually Gharda’s patent application says its PEK is tougher.
Development of Lignin-based Thermoplastics for Composite Applications [M23] by Amit Naskar, Oak Ridge National Laboratory, Oak Ridge, Tenn. (www.ornl.gov). Oak Ridge has a patented process for separating lignin from paper pulping solutions (U.S. Pat. # 7699958 in 2009) to make patent-pending thermoplastic lignin. Thermoplastic lignin from paper pulping isn’t totally new–Gehr Kunststoffwerk in Manheim, Germany announced something similar in 2005—but it’s unusual. The objective is recyclable bio-derived composites.
Effects of Hydrolytic Degradation on the Mechanical Properties of Renewable Bioplasics: Poly(trimethylene malonate) and Poly(trimethylene itaconate) [M32] by Ersan Eyiler, Mississippli State University, Starkville, Miss. (www.msstate.edu). Two renewable copolymers are being developed using a polycondensation reaction and monomers which are by-products from biorefining: glycerol, 1,3-propane diol, malonic acid, and fumaric acid.
Ester Functionalization and Structural Modification of Polypropylene via Solid-State Shear Pulverization [W5] by Jeanette Diop, Northwestern University, Evanston, Ill. (www.northwestern.edu). Reactive solid state sheer pulverizing of PP with benzoyl peroxide decomposes the peroxide into benzoyloxy radicals, which react with PP chains at near ambient temperature and introduce ester functional groups, which reportedly isn’t possible with reactive melt compounding.
Thermoplastic Starch and Polyethylene Blend for Blow Molded Bottle [T2] by Gregory Anderson, Teknor Apex Company, Pawtucket, R.I. (www.teknorapex.com). Teknor Apex applies its license for the patented starch/polymer alloys from Cerestech Inc. in Montreal, Canada (www.cerestech.ca) for the first time to extrusion blow molding. The new starch/HDPE masterbatch is made in two extruders. The first converts starch into thermoplastic, the second compounds it with HDPE for use in coex blow-molded bottles.
NANO MATERIALS AND COMPOSITES
Multifunctional Compounds Using Carbon Nanostructure Enhanced Glass Reinforcements in Electromagnetic Compatibility Applications[M5] by Desmond J. Van Houten, Owens Corning Science and Technology Center, Granville, Ohio (www.owenscorning.com). Carbon nanostructures are grown directly on glass fibers to make composites with metal-like conductivity for EMI shielding (U.S. Pat. Applic. # 20110124253, May 26, 2011). The technology was invented by Applied NanoStructured Solutions (www.appliednanostructuredsolutions.com), a unit of Lockheed Martin.
Creating Molecular Rebar from Multi-Wall Carbon Nanotubes [T19] by Kurt Swogger, Designed Nanotubes LLC, Austin, Texas (www.designednanotubes.com). A new high volume process can make high aspect ratio multi-wall CNT, called “Molecular Rebar” (U.S. Pat. Applications 2011041078, 2011075489, and 2010117392), which reportedly doesn’t need to be exfoliated during melt processing. Tire applications are already under development.
A Novel Method to Prepare PET Nano-Composites by Water Assisted Melt Compounding [W17] by Maryam Dini, Ecole Polytechnique de Montreal in Canada (www.polymtl.ca/en). Water is used to exfoliate a variety of nanoclays in PET nanocomposites. Various ratios of water to PET are tested.
Polymer Nanocomposite Foam for Textile Applications [M35] by Shu-Kai Yeh, National Taipei University of Technology in Taiwan (www.en.ntut.edu.tw). Nonwoven fabrics are foamed with cell sizes down to 1 nm and cell density of 3*1011cells/cm3. Four different polymers containing nanoclay nucleating agents were made into nonwovens, foamed and tested with TPU being the most promising.
Polymer Nanocellular Fibers via Supercritical Carbon Dioxide Based Extrusion Foaming [M35] by Wenyi Huang of Ohio State University in Columbus (www.osu.edu). Nanocellular TPU fibers formulated with nanoclay, CNT, and graphene nanosheets for nucleation were extrusion foamed using supercritical CO2 as physical blowing agent for 30%-50% lighter weight textiles than solid fibers.
A Method for the Evaluation of Respirators in a Nanorich Environment [T22] by Avraam Isayev, University of Akron in Akron, Ohio (www.uakron.edu). Processing with nanomaterials in production creates airborne hazards for operators, who wear respirators for protection. A device is built that simulates breathing to test how efficient respirators with different safety ratings are at stopping particles too small to see.